Cool that fine, that's answered my question.
Your taking the positive supply from outside the car from an AC to 12v DC transformer powered by the mains and you taking your Earth/GND from the car (the cars battery negative -)
That's just another reason, on top of the others why your having problems getting it to work correctly
What you need to do before you do anything else, is put that transformer back where it came from
And connect your camera to the cars electric system, your going to have to at some point anyway, so you may as well do it now, cos how your trying to power it at the moment is just putting you on a hiding to nothing.
Wire it all up how I described in my earlier post and hopefully, assuming you haven't damaged the camera, it should all work as intended.
Anyway let us know how you get on or you need help getting the 12 volt supply
Thanks for your help, maybe i did something wrong, or maybe the "relay" must be connected in other way...., anyway, i ended removing the camera relay, and i used mine and followed another tutorial, and works now!!! i still have few interferance but i can see what is behind now,
i read i need a filter, a 10,000µf capcitor as filter,i cannot find yet, but at least is working with some lines but i can see at least,someone else using the capacitor as filter or do you know what can i use as filter?
and thanks to all for the help!!!